title: A survey of sleep deprivation patterns and their effects on cognitive functions of residents and interns in Korea.
abstract: OBJECTIVE
  To investigate the effects of sleep deprivation on physical health, cognition, and work performance in residents and interns who suffer from chronic sleep deprivation.
  
  
  METHODS
  Fifty-eight residents and interns were recruited in this study. They completed sleep diary for 2 weeks and questionnaires including health complaints, daytime sleepiness and work performance, and were evaluated with actigraphy. Stroop test, continuous performance test (CPT), trail-making test (TMT) and Korean-California verbal learning test (K-CVLT) were done as neuropsychological evaluations. Subjects were divided into severe sleep deprived (S-SD, average night sleep less than 4 h), mild to moderate deprived (M-SD, 4-6 h), and non-sleep deprived (Non-SD, more than 6 h) groups.
  
  
  RESULTS
  Forty-one subjects (70.7%) were sleep-deprived. Mean sleep duration was 5.0±1.2 h/night and work duration was 14.9±2.7 h/day. The S-SD group showed higher Epworth Sleepiness Scales than M-SD and Non-SD groups. Severe sleep deprivation was associated with higher level of stress, more frequent attention deficit, and difficulty in learning (P<0.05), but not with decreased neuropsychological test results.
  
  
  CONCLUSIONS
  These results suggested that sleep deprivation in residents and interns might affect their health as well as work performance that might influence the quality of patient care, although active compensatory brain mechanisms could be involved to preserve their performance.
authors.affiliation: Department of Neurology, Ewha Womans University, School of Medicine and Ewha Medical Research Institute, Seoul, Republic of Korea.
authors.forename: Hee Jin
authors.initials: HJ
authors.lastname: Kim
authors.forename: Jee Hyun
authors.initials: JH
authors.lastname: Kim
authors.forename: Kee-Duk
authors.initials: KD
authors.lastname: Park
authors.forename: Kyoung-Gyu
authors.initials: KG
authors.lastname: Choi
authors.forename: Hyang Woon
authors.initials: HW
authors.lastname: Lee
mesh_terms: D056044:Actigraphy; D000328:Adult; D001288:Attention; D002908:Chronic Disease; D003071:Cognition; D005260:Female; D006306:Health Surveys; D006801:Humans; D007396:Internship and Residency / Q000706:statistics & numerical data*; D008297:Male; D008499:Medical Records; D008505:Medical Staff, Hospital / Q000706:statistics & numerical data*; D009784:Occupational Diseases / Q000453:epidemiology*; D056910:Republic of Korea / Q000453:epidemiology; D012892:Sleep Deprivation / Q000453:epidemiology*; D012894:Sleep Stages; D012919:Social Behavior